Liquid ejecting apparatus and drive circuit

Abstract

A liquid ejecting apparatus includes a drive circuit that outputs a drive signal, wherein the drive circuit includes a modulation circuit that modulates a base drive signal to output a modulation signal, an amplifier circuit that amplifies the modulation signal to output an amplified modulation signal, a demodulation circuit that demodulates the amplified modulation signal to output the drive signal, and a substrate on which the modulation circuit, the amplifier circuit, and the demodulation circuit are provided, wherein the substrate includes a first face and a second face opposite to the first face, wherein the demodulation circuit includes a first coil and a second coil electrically coupled in parallel with the first coil, and wherein the first coil is positioned so as to overlap at least part of the second coil in a direction normal to the first face.

What is claimed is: 
     
       1. A liquid ejecting apparatus comprising:
 a liquid ejection head including a drive element, the liquid ejection head ejecting a liquid by a supply of a drive signal to the drive element; and 
 a drive circuit that outputs the drive signal, wherein 
 the drive circuit includes 
 a modulation circuit that modulates a base drive signal to output a modulation signal, 
 an amplifier circuit that amplifies the modulation signal to output an amplified modulation signal, 
 a demodulation circuit that demodulates the amplified modulation signal to output the drive signal, and 
 a substrate on which the modulation circuit, the amplifier circuit, and the demodulation circuit are provided, 
 the substrate includes a first face and a second face opposite to the first face, 
 the demodulation circuit includes a first coil and a second coil electrically coupled in parallel with the first coil, 
 the first coil is positioned so as to overlap at least part of the second coil in a direction normal to the first face, and 
 the first coil is provided on the first face, and the second coil is provided on the second face. 
 
     
     
       2. The liquid ejecting apparatus according to  claim 1 , wherein
 the first coil and the second coil are positioned so that a first magnetic flux generated in the first coil and a second magnetic flux generated in the second coil are superposed. 
 
     
     
       3. A drive circuit that outputs a drive signal for driving a drive element, the drive circuit comprising:
 a modulation circuit that modulates a base drive signal to output a modulation signal; 
 an amplifier circuit that amplifies the modulation signal to output an amplified modulation signal; 
 a demodulation circuit that demodulates the amplified modulation signal to output the drive signal; and 
 a substrate on which the modulation circuit, the amplifier circuit, and the demodulation circuit are provided, wherein 
 the substrate includes a first face and a second face opposite to the first face, 
 the demodulation circuit includes a first coil and a second coil electrically coupled in parallel with the first coil, 
 the first coil is positioned so as to overlap at least part of the second coil in a direction normal to the first face, and 
 the first coil is provided on the first face, and the second coil is provided on the second face.